No One Left Behind

Mass Effect 2 is one of my favorite games of all time. The characters, the story, and the way the final act brings everything together make it, to me, a masterpiece.

I still remember leaving university and heading straight to GameStop to pick it up in January 2010. I went home, started playing, and within minutes, the SSV Normandy was destroyed, and Commander Shepard was dead. My snacks weren’t even ready. That didn’t matter, though; it was going to be a long night, and by then I already knew I wouldn’t go to class the next day.

Sixteen years later, BioWare, the studio behind the game, announced it would close. The news made me think about that night in January 2010, the people who created the game, and the millions of players who, like me, became attached to its characters and universe.

With that in mind, I decided to say goodbye by turning to some player data. Steam’s achievement statistics from the Mass Effect Legendary Edition, released in May 2021, offer a glimpse into how players have experienced the game over time. Early in the game, a mysterious figure known as the Illusive Man brings Shepard back to life. From there, Mass Effect 2asks us to assemble a squad, earn its trust, and lead it into something literally called the Suicide Mission. As the name suggests, not everyone is guaranteed to come back. Having spent an entire game getting attached to this crew, I wanted to see how often players managed to bring them home.

Whether these characters survive depends on the choices you make throughout the game. Answer a question the wrong way or antagonize them, and their chances of surviving will drop. And it all begins with a simple decision: recruiting them.

Some of the twelve potential squadmates are optional, so you can finish Mass Effect 2 without recruiting all of them. I can’t imagine why someone would leave Tali behind, but plenty of players never unlocked her recruitment achievement. Some may have skipped her; others may have stopped playing before reaching her mission. To make sense of those numbers, we first need to look at what Steam is counting.

There’s a catch with these numbers: Steam tracks achievements across the entire Legendary Edition, a compilation that includes the first three Mass Effect games. These percentages also include players who never started Mass Effect 2. To get a better approximation, I used Mass Effect 2’s opening achievement, Missing in Action, as a rough baseline. In my October 21 snapshot, 40.2% of players had unlocked it, while 27.3% had earned the achievement for finishing ME2. That suggests roughly 68% of players who started the game had also finished it.

Using the same baseline, approximately 76% had recruited Tali. The remainder could include people who stopped playing before reaching her recruitment mission, so it doesn’t tell us how many deliberately left her behind. Figure 1 shows the recruitment percentage for all optional characters. Legion, my favorite from this group, sits at the end of the chart with 68.9%.

Now suppose we’ve recruited everyone and assembled the best crew in the galaxy. The next step to ensure their survival is to complete their loyalty missions. Completing the missions doesn’t automatically guarantee survival, but skipping them hurts their chances. Every character has their own problems and flaws, and to me, this is where the game shines. Throughout the game, they confide in you about these and invite you to help them solve them. An example is Thane’s Sins of the Father mission, where Thane learns his son has taken an assassination job and wants to find him before he carries it out.

The data says that most of the time, players completed their loyalty missions. Kasumi, the thief, has the highest completion percentage, at almost 80%. A curious result, considering Kasumi wasn’t included in the original 2010 release, and the only way to get her was through a downloadable add-on that cost $7. While we cannot know for certain why she tops the loyalty rankings, one possibility is that players who skipped the add-on back then finally got to experience her story, since the Legendary Edition includes it. Or maybe it’s simply because her mission, a heist to recover an item belonging to her former partner, is one of the coolest and most unique in the game. Figure 2 shows the loyalty mission completion percentages for all crewmates.

Strap in. We’re going through the Omega 4 Relay, and I can’t guarantee we’ll come back. Using the same baseline as before, 68% of players who started Mass Effect 2 finished it, and the same share earned the achievement for bringing Shepard home alive. To be precise, this doesn’t mean Shepard survived every ending, since you can earn both achievements on different playthroughs. But for the sake of a happy ending, let’s say Shepard made it back from the Collector Base every time. Otherwise, it’s truly the end, and you won’t be able to start Mass Effect 3 with the same save file.

As for the squad, I have good news: every squadmate survived the Suicide Mission at least 90% of the time. But first, a note on where that number comes from. Steam’s achievements don’t track survival for each character. The only relevant point is an achievement you earn if every squadmate makes it out alive. About 53.5% of players who started ME2 earned this accolade, No One Left Behind. On Xbox, the version I played, I was one of those who got the happy ending (not to brag, but I actually earned all the achievements).

While looking for data to write this article, I remembered that in 2021, the year the Legendary Edition launched, EA released an infographic with the survival rate for each squadmate. Those numbers are quite old, but they offer a view into one of the main questions I wanted to answer with this analysis: Who gets left behind? Figure 3 shows the numbers.

Mordin, the Salarian scientist, is the character least likely to survive the mission. But why, right? There must be some explanation, or at least an informed guess we can make. After all, Mordin, as far as I know, is one of the game’s most popular characters, and his loyalty mission completion rate is above average. So, I looked around in old forums, remnants of the Internet I used to love, and found one where user themikefest explains that in Hold the Line, one of the segments of the Suicide Mission, all characters have a hidden defense score that, combined with their loyalty, determines if they can hold said line. Apparently, Mordin has the lowest defense score, making him particularly vulnerable if something goes wrong. The very model of a scientist Salarian who has studied species like Turian, Asari, and Batarian (seriously, play the game if you haven’t) isn’t alone at the bottom. Tali, Kasumi, and Jack share the same score.

Garrus has one of the highest defense scores in the game, making him considerably harder to kill. He also has the highest cool factor, or aura, as young people say. I guess having a former C-Sec officer watching your back does help.

This game is truly something else. From its shocking beginning to its high-stakes finale, and with a group of characters worth fighting for in between, Mass Effect 2 is a game that, sixteen years later, still lives in my head.

BioWare may be closing its doors, but the worlds and characters aren’t going anywhere. Now, excuse my cheesy line, but Shepard came back from the dead once, and while I don’t know if Mass Effect will ever get another chance, I like to think it still has a future somewhere in the galaxy.

Meanwhile, I’ll remember the Normandy SR-2, its crew, and that night in January 2010 when I decided saving this galaxy was more important than attending Calculus class the next morning.

Thank you, BioWare.

Sources:

• Steam Global Achievement Statistics, Mass Effect Legendary Edition: https://steamcommunity.com/achievements/1328670. Data retrieved October 21, 2026. Percentages adjusted using the Missing in Action achievement as a baseline.
• Suicide Mission survival rates: https://gameinformer.com/2021/12/20/poor-mordin-mass-effect-suicide-mission-survival-rates-revealed
• Suicide Mission defense stats thread via BioWare Social Network: https://biowaresocialnetwork.boards.net/thread/51/me2-mission-guide

You can find the datasets and charts on my GitHub: https://github.com/juandes/data-experiments/tree/main/masseffect-2

Charts were made with RowSwift, my iOS app for exploring and visualizing CSV data: https://apps.apple.com/us/app/rowswift-data-explorer/id6749399145